This is accomplished via two new `TObject` methods: `has_own_virtual` and `call_setter`. If an object does not contain it's own version of a property, it will first crawl the prototype chain to see if there is an overwritable virtual. If so, it will invoke that prototype's setter.
A bit of borrow finangling was required to do this; `super` now no longer caches it's proto and constr values and instead dynamically constructs them. This also means it can't be downcasted to `Executable` anymore.
With this commit, virtual setters and super-setters now work correctly.
A base prototype is only applicable in cases where a method is being called as a property on an object. Bare function calls, `apply`/`call` calls, and so on do not generate a base prototype.
We also add a convenience method, `call_method`, to all objects. This method automatically calculates the correct base prototype for a method call on an object, which is the only operation that should generate base prototypes.
Nathan Adams